create_draft_reply · Gmail Assistant MCP: Risk & Policy

WHAT IT DOES

What create_draft_reply does on Gmail Assistant MCP

AI agents use create_draft_reply to create or update resources in Gmail Assistant MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Gmail Assistant MCP environment.

WHY IT NEEDS A POLICY

Why create_draft_reply needs a policy

This tool creates new email drafts in Gmail, which is a reversible write operation. It does not delete, execute arbitrary code, move money, or perform irreversible actions. The severity is medium because an agent could compose misleading, abusive, or deceptive emails on behalf of the user, but the drafts are not automatically sent (requiring user review before dispatch), limiting immediate blast radius.

From the tool's definition The tool explicitly 'Generate[s] an AI-powered draft reply to an email and save[s] it in Gmail' — this is a create/write action that modifies Gmail data by adding new draft messages.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_draft_reply Rate-limited

create_draft_reply stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "create_draft_reply": {
      "limits": [
        {
          "counter": "create_draft_reply_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Gmail Assistant MCP, so you can run agents against it safely.

FAQ

Questions about create_draft_reply

What does the create_draft_reply tool do? +

Generate an AI-powered draft reply to an email and save it in Gmail. It is categorised as a Write tool in the Gmail Assistant MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create_draft_reply? +

Register the Gmail Assistant MCP server in PolicyLayer and add a rule for create_draft_reply: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Gmail Assistant MCP. Nothing to install.

What risk level is create_draft_reply? +

create_draft_reply is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit create_draft_reply? +

Yes. Add a rate_limit block to the create_draft_reply rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block create_draft_reply completely? +

Set action: deny in the PolicyLayer policy for create_draft_reply. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides create_draft_reply? +

create_draft_reply is provided by the Gmail Assistant MCP server (thejoefriel/gmail-assistant-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.